1. Field of the Invention
The present invention relates to a method and apparatus for infusing a pressurized viscous fluid, such as for use in endoscopy.
2. Description of the Prior Art
The use of fluids, particularly water, saline or air in examinations of hollow internal organs, such as in conjunction with cystoscopes, proctoscopes and gastroscopes, is well known. In addition, the use of such fluids via an endoscope to distend an internal organ for improved viewing of the organ is also known in the prior art. Examples of prior art systems for directly introducing pressurized air, or a fluid such as water or saline, into an internal organ for endoscopic examination thereof are illustrated in U.S. Pat. Nos. 1,345,406 and 2,236,842. Other examples of elaborate prior art valving arrangements for introducing fluid into a hollow organ to inflate the organ are disclosed in U.S. Pat. Nos. 1,741,740; 1,453,975; 3,570,448 and 3,239,074. In addition, the concept of an inflatable pressurized cuff for transferring pressure from the inflatable cuff to provide a pressure infusor, is well known, such as, by way of example, the type of pressure infuser available from Fenwal Labs under designation no. FT123, as well as, by way of example, the type of pressurized cuffs disclosed in U.S. Pat. Nos. 3,468,308; 3,228,395; Re. 26,006 and 3,054,401. None of the prior art known to applicant employed a viscous fluid for minimizing distortion of an image of the interior of the organ viewable through an endoscope which flowed sufficiently freely at room temperature to enable it to readily be used quickly enough in order to inflate the uterus so that all parts of it can be viewed while simultaneously not distoring images viewed through the hysteroscope. Previously, in utilizing this viscous fluid, it had to be withdrawn into a sterile syringe which was then attached to sterile tubing and forced into the hysteroscope thereby requiring more than one person to accomplish the hysteroscopic examination of the patient; one person being required to control the infusion of the viscous fluid into the uterine cavity through the hysteroscope and another person being required to actually accomplish the hysteroscopic examination. These disadvantages of the prior art are overcome by the present invention.